Method and apparatus for covering balls



Dec. 10, 1940. w. J. vol-r -ErAL METHOD AND APPARATUS FOR COVERING BALLS 2 Sheets-Sheet l 6d.. M 5 Z 3253.0 W Z 5 652V 5%@ W @w z, n.. W 2 4 W 73 2 I F J 5 l www H I Y W ,A/ l 2v PRESS URE Dec. 10, 1940. w. .1. volT ETAL METHOD AND APPARATUS FOR COVRING BALLSl 2 Sheets-Sreet 2 Filed Jan. 24, 1959 BY HAR/em, K/ECH, Fo

E & HARRAS FOR THE FIRM Patented Dec. 10, 1940 UNITED STATES PAT METHOD AND APPARATUS Foa COVERING BALLSv william J. voit, Los Angeles, and Leith o. weimar, Southgate, Calif.; said Weimer-asslgaor to said Voit Application January 24, 1939, Serial No. 2525602 7 claims.

This invention relates-to a method and apparatus for covering balls, and has as itsobject to provide a method and machine for applying sheets of rubber or similar material to curvilinear solid objects, as for instance in the process of manufacturing game balls or other objects comprising an enveloping wall or cover of such material. It is especially adapted to the application of a spherical or spheroidal rubber envelope l0 to the core of a baseball of the soft ball type, but is capable of use for many other purposes. While for purposes of illustration only, the invention will be described as embodied in a machine for applying an envelope of sheet rubber to the core of a baseball of the soft ball type, we do not wish the scope of our invention to be limited to such an embodiment.

In the manufacture of baseballs of the kind described in our Patent No. 2,127,487, a cover of rubber is applied to the core. Our application for Patent Serial No. 236,856 describes a baseball which has an inner wall of rubber enveloping a fibrous core, and an outer rubber cover with an intervening wall oi' fibrous material. Sections or pieces of unvulcanized rubber material for these covers or inner walls are placed in position upon the ball center or core, and the assembled article is placed in a vulcanizing mold, where the rubber is vulcanized into a continuous integral envelope.

It is the object of the present invention to provide a method oi and a machine for-the application of the sections of rubber to the ball center in preparation for the vulcanizing operation. It is the purpose of the invention to provide a method and a machine Which will rapidly and eiliciently accomplish this operation.

It is a further object of the invention to pro-y vide a method and a machine which will apply o the rubber sections in such a manner that the finished envelope shall be of even thickness and without folds-or seams or thickened portions. The attainment of such a purpose is of great value in the manufacture of baseballs, If either van inner rubber envelope or a rubber cover, and especially the rubber cover, is of uneven thickness in the finished ball, there follow a number of undesirable results. Balls with covers of varying thickness also develop soft spots. When the ball is compressed in the vuleanizing mold, areas of relatively greater density form in the vicinity of the thickened portions of the cover. In the intervening areas'of lesser density the particles of brous material of the center are more readily capable of motion" with respect to each other under the impacts to which the ball issubjected in play, with' the result that these spots become increasingly softer, while the more compact areas tend to retain their original 'rigidity to a greater degree. Suchuneven distribution of'the'rubber 5 material in the cover causes uneven resiliency, resulting in uncertainty and undesirable variation in the character of the performance of the ball in play. Such uneventhickness also presents an uneconomical use of material. The useful lifev 10 of the ball is measured by the thinnest portion of its cover. When the coveris worn through at such a thin area, the rubber material'in the balance of the cover becomes wasted and of no value.

In the drawings: i Fig. 1 is a front elevation of a bodying our invention.

Fig'. 2 is an end elevation thereof. l

Fig. 3 is a top plan view of the machine.

Fig. 4 is an enlargedvertical section ot the 20 former and parts of the machine adjacent thereto, taken along the line I-l of Fig. 1.

Fig. 5 is an enlarged horizontal topplan view of the lower half of the former as indicated yby the line 5 5 of Fig. 1. g5

Fig. 6 is an enlarged horizontal bot-tom plan view of the upper half of the former as indicated by the line 6-6 of Fig. 1.

Fig. 7 is a fragmentary vertical section of a modified form of the former.

Fig. 8 is a vertical elevation ofthe former and adjacent frame members of the machine, showing the two parts ofthe former in separated position with a lball placed ready for application of the cover material. y y

Fig. 9 is a similar view showing the two parts of the former brought together upon the ball.

The supporting frame ofsthe machine consists of front uprights II, rear uprights I2, lower horizontal braces I3, a front diagonal brace I l, a rear diagonal Ibrace I5, and lve `upper horizontal rectangularly arranged channel beams I6, IIia and Il, Ila, and llb. A horizontal plate I8 rests upon the channels I6, I6a and I1, I'Ia and is bolted to channels I1, IIa at I9, I9. The plate I8 is circular in form with two projecting arcuate shaped ears` 20, 20. The bolts I9, I9 pass through these ears 20, 20 and the channels I1, Ila and secure the plate I 8 against horizontal displacement.

vA former for shaping a .rubber cover or envelope upon the bally is generally designated by the letter A. It has an. upper half 2| and a lower half 22, each` of which is a hemispherlcal shell, and each of which has welded thereto at its 55 15 machine Vems nements: piste-chica is aan vin the case oi theupperhalt and I4 in the case oi the' lower half. The lower shell I! is provided witha downwardly extending cylindrical .boss 2l winch extends into a recessII-in the upper race oi the plate Il and is supportedthereon in air-tight relationship with the bottom Afacev i oi the recessby means of a'gasket Il. -The shell Il ish'eld 1.11 position upon'the plate il., kand the boss Il is clamped tightly against the plate I8, by means oi four stud bolts Il, vthreaded atl their upper ends into the lowerv tace oi the platev s 24, and secured at theirl lower 'ends to the plate their lower ends into the upperv facevo! the plate' 2l and secured at theii'vuppe ends to the plate Il by nuts 32. .A circular boss I8 projecting from the topy oi the, upper shell Il projects through an alignedf-centralaperture Il inthe The lowershell is rigidly mounted upon the l 'stationary plate I8. 'The upper shell is rigidly mounted-upon the plate i. which is vertically I movable insuch a manner'that the upper shell can beplaced incontactwith thelower shell -to elevated above thelower shellfor insertionl o! a it is rigidly secured to aci-oss channel ss, which is in turn rigidly carried by two Islide rods I1."-

These two slide rods are vdisposed in two sleeves Il which are secured respectively at the two extremities of the ears Il of the plate It, and the rods are tied togetherat their lower ends by a cross channel It. A pneumatic plunger rod Il isl carried by the channel il midway of the length oi the channel. This plunger rod isk associated in the usual manner of pneumatic .jackswith a lpneumatic -cylinder Il which is lin susupper end of the cylinder Il and .the plate .IlV

ailords an air-tight seal-between'th'ese two parts. By means of an air pressure pipe system u'. which is connected to a source oi air pressure (not shown) by a pipe Il, and bythe operation of a two-way valve 48a which controls the iiow oi' air to the ends o! the pneumatic cylinder 4i. the plunger rod 40 may be moved vertically up or down to separate or'bring together the .two shells 2| and 22.- v .v

An air vacuum pipe is connected at 41 to a).

pipev Il leading to a vacuum pump orvacuum chamber (not shown), and-an air pressure pipe ,Y

a is connected through avalve Agwiththe pressure pipe u. The vacuum air pipe dl is branched toprovide two pipes Il, Il. oifwhichll is connected by pipe l! to the upper shell, and Il is connected by pipe BI to the lower shell. The branch pipes 50 and li are Joined at their upper `ends where both are connected to the pressure pipe lla. The connections oi'thebranch pipes Il and li with pipes I2 and I3 are located be- 'tween the vacuum pipe and the pressure pipe "a: valves Il and Il are provided in branch pipes lll and li respectively, between the vacuum pipe Il and the connections to pipes l! and Il; and

v'saisissante n aand the` connections to pipes Iz and Il 'Valves Il and Il are tied together and operatel.

in unison by a handlever Il. Valves II and la' are tied together and .operated in unison by s hand lever -l.. By this arrangement oi pipes and 5 valves. either superatmospheric air pressure or e subatrnospheric air vpressure can. be applied simultaneously to the two shells 2i and 22. .The

` valve Il isv normally open 'when the machine is being operated. A relieil vent is provided at Il l0 to prevent the application oi sudden excessive pressures tothe operating partsoi the machine.

The pipe l2 is connected t6 a ilexible air hose Ila. This hose permits movement of the upper l shell 2i while vai: the same time maintaining 16 pneumatic connection between the pipe l2 and air ducts formed in the shell. Ducts I I lead from interior o! shell Il atthe upper central point ereof through the boss Il to one end of an air 4pipe I! which is connected at u to the ilexible 20- hose lla. An annular recess yN in the lower face of the plate 2l is connected by a duct 84 to the other end o! the air pipe 82, and is thereby placed `in pneumatic connection with the ilexible hose j lla for the application of air pressure or air 25 suction. l

'Ihe pipe Il is branched at 85. One branch pipe leads to'an air duct which is formed in iorm a spherical former `chamber ll. or can be plate Il and the boss l! and opens into'the v l d. interior oi the lower shell 22. The other branch ball or ball making materialin the former A.V To! provide for this vertical movement ofthe plate Il..

pipe IIb leads to an air duct 61 i'ormedin the .plate Il which communicates pneumatically with an annular recess Il in the upperl face o! the simultaneously to the interior of the and 22 andrecesses il and 89.'.

` A ioraminous rubber diaphragmr'llis disposed in horizontal position across the rim o! the lower shells 2| shell n, and the periphery 1Il of this diaphragm 4 is secured between a iasteningring 12 and an f annular recess 'ilinv the plate 24 vby means of screws 1l. .A similarioraminous rubber diaphragm: 1i is disposed in .horizontal position across the rim oi the upper shell 2|, and its peripheral portion 'Ihl'is secured between a fastening ring 11 and an annular recess 'Il in the vplate 23 by means of screws il.A 'l'.hese rubber diaphragms are perforated as at 80 and respectively (see Figs. 5 and 6). They are .made with a .progressively increasing thickness i'rom periphery to center. the correlation of tensile strength and thickness being such that when the diaphragm is caused to assume ahemispherical position incontact with the inner face oi its .55* corresponding shell, anygiven portion of the surv face oi the diaphragmfwill increase in area' in r oi the machine, the upper hemispherical shell is elevated by admitting air vunder-pressure-to the lower end o: the cylinder 4I. A sheet Il o! stock rubber (see Fig. 8) oi uniform thickness is placed in position on top of and in contact with thelower diaphragm 1I, extending over and substantially covering the lower plate 2l. Another similar sheet oi rubber 8l is manually held lust beneath the upper dia- 1l, withl its coated side down. The lever Il is then thrown to position to ap- '1s ply air suction simultaneously to the interior of fannular recess 13 in theplate'. and a fasten;

the shell 22, to the annular recess Il, tothe interior of the shell 2|, to the annular'recess 88, and the annular recesses 82.. The vacuum set 8 up within the recess 88 serves to hold the outer portions of the rubber sheet 8l immovable with respect to'the plate 2 4. The: remainder of the sheet of rubber is caused to adhere to the rubber diaphragm 18 without displacement'A relative 10 thereto, by reason of the reduction below atnios-` pheric normal of the air pressure within the shell, and the transmission of this subatmospheric pressure through the perforations 88 to the under surface of the sheet of rubber.

' *1gV As the reduction of air pressure within the shell continues, the diaphragm 18 and the sheet of rubber 84 immovably. attached thereto, move downward, .until the 'diaphragm comes tov rest in' contact throughout .its area withthe inner face M of the hemispherical shell. Due to its progressively increasing thickness from periphery to cen.-

ter, the diaphragm resists stretching to a progressively greater degree from periphery to lcenter. The sheet/of rubber is thereby caused to 28 be stretched in progressively less degree from periphery to center. If the diaphragm is not used,-

the sheet of rubber when drawn'to the' bottom ofthe shell, will be progressivelythinner from periphery to center. By disposing a diaphragm so below the sheet of rubber to control in compensatory fashionvthe tensile forces which act to stretch the sheet of rubber in all directions as it is drawn into the-shell, the sheet when it as sumes its ilnal position in contact with the inner 8l face of the shell, is of substantially uniform thickness throughout its area.

At the same time that the sheet ofrubber 8l is thus being drawn into position in such a manner as to stretch it lto uniform thickness, 40 the upper sheet of rubber I8 is in the same fashion and for the same reason being drawn up intov position within the upper hemispherical shell.

The small recesses 82 serve'to hold the corners of the rubber sheet 86 in position against the acs tion of gravity.

f A ball center 88 of kapok or other desired material which has preferably been coated with rubber cement is then placed within the lower shell, resting upon the sheet oi' rubber 8l. The pneumatic cylinder" is then operated to lower the upper shell until the peripheral portion of 'the sheet of rubber 88 contacts the peripheral portion of the sheet of rubber 8l, and the central portion of the sheet of rubber 88 contacts the upper surface of the ball center 88. The pneumatic .jack is preferably used at this juncture to. apply suiiicient pressure to unite the peripheral edges of the two sheets of rubber. Air pressure within the cylinder 4| is then released; sumcient air w pressure is applied to the interior chambers of the two shells, and to the recesses 88 and 88, to release the kapok center, which is now provided l vwith a. rubber envelope of uniform. thickness throughout; the pneumatic jack is used to eleg5 vate the upper shell; and the covered ball is removed to the next operation of its manufacture.

The projecting rim formed by the union of the two peripheral edges of the upper and lower pieces of the rubber cover of the ball is removed in any suitable manner. Fig. 7 shows an alternative form of the invention in which a convenient means is provided for removingthis pro- Jecting rim at the time the cover parts are applied. 'I'he periphery 18' of a diaphragm 'I Sf.' is secured between the inner lateral wall of the Y l sistance.

ing ring 11' seated within the recess. 'I'his fastening ring' proiects slightly fromthe face' of the 'One embodiment of the inventionis shown and f f described'herein., Theinventionis applicableto 10 i a wide variety o f `uses, and under any conditions-v in which va sheet of rubber or other materialhaving thephysical propertiesv of rubber is in a manufacturing process'v or other 'manipulation' caused to undergo achange of curvature where- 15" by its thicknesis .changedin varying degrees at j v different points ofl its area.V Certain features `oi! the invention may befusedindependently o ffother featurea'and'sucli independent use is within the scope of the invention.'l y v Q ,20

We claim as our invention:

1. In a machine for applying arubber n to a ball; thecombination of:two hemispherical formers mounted with .their open sides'iffacing each other, each of said iformersbeir'ls provided it` with an annular' face adapted'to vcontact-theaunular-face ofthe other ofsaid forn'iers,` and each 'of'said facesbeing kprovided with anfan'nular ref cess; means for moving said formers into registering contact andfor separating said formera: a.k

foramino'us diaphragm 'of elastic materialmounted across the open side of each of said formers with its peripheral, portion in vair-tight' relationship with" said `annular face oi'rits associated fermer and with its periphery spaced radially ins' v.wardly from said annular recess; and means for establishing subatmospheric pressure simultaneously within said recesses and said formers. 2. A method of applying a rubber envelope to a ball, comprising the steps of: initially securing the 40 peripheral portion ofa'\sheet of rubber vagainst movement with -respect to the center yof said sheet; subsequently deformingthe central portien of said sheet from a plane to a .hemphgm `and simultaneously providing resistance tothe. 45

tensile stresses vthereby set up. within said sheet.l said resistance .being provided in a progressively l increasing degree from periphery to center of said central portion, and said resistance beingy -v A' other than that afforded by the material ofsaid 60 sheet; similarly operating upon a second sheet'of rubber; applying said two hemispherically shaped sheets uponV opposite sides of a ball; securing said sheets to said ball;` and withdrawing said re- 3. A method of applying a rubber envelope to v a bail, comprising the steps of: initially securing the peripheral portion of a Vsheet of` rubber against movement with respect to the center of said sheet; subsequently deforming a circular 60 A similarly operating upon a second sheet of rub- 70 v ber; applying said two hemispherically vshaped sheets upon opposite sides of a ball: securing said lsheets to said ball; and withdrawing saidresistance.k

` 4. In a machine for applying elastic 78 tion of: an open-sided former having a spheroidal 'cavity and an annular edge face extending laterall! away from the edge oi said cavity; a foramisecured to said former in position across the open aide oi saidformer, the thickness of ma cnaphragm increasing progressively from periphery to center.; means for peripherally securinga sheet of elastic material to said annular edge face; and a means for establishing sub-atmospheric pressure within the chamber between said former and said diaphragm.

p 5. In -a machine for applying elastic material in =sheet form to spheroidal objects, the combination of: an open-sided '.ormer having a hernispheroidal cavity and an annular edge face .extending laterally away from the edge of said cavity; a ioramlnousdiaphragm of elastic material mounted across the circular open side of said former, and peripherally secured to said annular edge face at points radially outwardly from the V-edge of said cavity, the thickness of said diaphragm vincreasing progressively from periphery Ato center; annular means on said 'annular edge spheroidal cavity and an annular edge face extending laterally away from the edge of said cavity; a foraminous diaphragm of elastic material aaaasss means for establishing sub-atmospheric pressure Y within the chamber between said former and said diaphragm and in said annular recess means.

'1. In a machine for applying a rubber envelope to a ball, the combination of: two formers Amounted in axial alignment with their open sides facing each other, each having a hemispheroidal cavity and an annular edge face extending laterally away from the edge of said cavity; two for- 'aminous diaphragms of elastic material mounted across the circular open sides of said formers respectively,.and peripherally secured to said annular edge faces at points radially outwardly from the edge of said cavities, the thickness of said diaphragms increasing progressively from periphery to` center; annular recess means o'n each of said `annular edge faces disposed radially outwardly from said points for securing a sheet of elastic material contiguously upon each of said diaphragms respectively; means for establishing sub-atmospheric pressure within said cavities and saidy annular recess means; and means for moving said formers together with their open sides in registry and for separating said formers.

WILLIAM J. von'. Lm C. WEIMER. 

